Fix npt of webhook notify (#1474)

Co-authored-by: zhengqiwei <[email protected]>
Co-authored-by: tomsun28 <[email protected]>

manager/src/main/java/org/dromara/hertzbeat/manager/component/alerter/impl/WebHookAlertNotifyHandlerImpl.java

@@ -17,15 +17,21 @@
 
 package org.dromara.hertzbeat.manager.component.alerter.impl;
 
-import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
+import org.apache.commons.lang3.StringUtils;
 import org.dromara.hertzbeat.common.entity.alerter.Alert;
 import org.dromara.hertzbeat.common.entity.manager.NoticeReceiver;
 import org.dromara.hertzbeat.common.entity.manager.NoticeTemplate;
 import org.dromara.hertzbeat.manager.support.exception.AlertNoticeException;
-import org.springframework.http.*;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Component;
-import org.springframework.web.client.RestTemplate;
+
+import java.util.Iterator;
+import java.util.Map;
 
 /**
  * @author <a href="mailto:[email protected]">Musk.Chen</a>
@@ -39,8 +45,12 @@ public void send(NoticeReceiver receiver, NoticeTemplate noticeTemplate, Alert a
         try {
             HttpHeaders headers = new HttpHeaders();
             headers.setContentType(MediaType.APPLICATION_JSON);
+
+            // fix null pointer exception
+            filterInvalidTags(alert);
             String webhookJson = renderContent(noticeTemplate, alert);
             webhookJson = webhookJson.replace(",\n  }", "\n }");
+
             HttpEntity<String> alertHttpEntity = new HttpEntity<>(webhookJson, headers);
             ResponseEntity<String> entity = restTemplate.postForEntity(receiver.getHookUrl(), alertHttpEntity, String.class);
             if (entity.getStatusCode().value() < HttpStatus.BAD_REQUEST.value()) {
@@ -58,4 +68,25 @@ public void send(NoticeReceiver receiver, NoticeTemplate noticeTemplate, Alert a
     public byte type() {
         return 2;
     }
+
+    private void filterInvalidTags(Alert alert) {
+        if (alert.getTags() == null) {
+            return;
+        }
+
+        Iterator<Map.Entry<String, String>> iterator = alert.getTags().entrySet().iterator();
+        while (iterator.hasNext()) {
+            Map.Entry<String, String> entry = iterator.next();
+            if (StringUtils.isNoneBlank(entry.getKey(), entry.getValue())) {
+                continue;
+            }
+
+            iterator.remove();
+        }
+
+        // In order to beautify Freemarker template
+        if (alert.getTags().entrySet().size() <= 0L) {
+            alert.setTags(null);
+        }
+    }
 }

manager/src/main/resources/templates/2-WebhookTemplate.txt

@@ -8,9 +8,11 @@
   "times": ${times},
   "triggerTime": "${triggerTime}",
   <#if (restoreTime??)>"restoreTime": "${restoreTime}",</#if>
+  <#if (tags??)>
   "tags": {
     <#list tags as key,value>
-      "${key}": "${value}",
-    </#list>  
+    "${key}": "${value}",
+    </#list>
   }
+  </#if>
 }

manager/src/test/java/org/dromara/hertzbeat/manager/component/alerter/impl/WebHookAlertNotifyHandlerImplTest.java

@@ -1,12 +1,15 @@
 package org.dromara.hertzbeat.manager.component.alerter.impl;
 
+import lombok.extern.slf4j.Slf4j;
+import org.dromara.hertzbeat.manager.AbstractSpringIntegrationTest;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
 /**
  * Test case for {@link WebHookAlertNotifyHandlerImpl}
  */
-class WebHookAlertNotifyHandlerImplTest {
+@Slf4j
+class WebHookAlertNotifyHandlerImplTest extends AbstractSpringIntegrationTest {
 
     @BeforeEach
     void setUp() {